Last May, Boston police conducted a massive sweep of men and women they described as drug offenders terrorizing the streets of Roxbury, the culmination of a five-month investigation dubbed Operation H that officials said would send a chilling message to anyone else looking to wreak havoc.

“This operation demonstrates the Police Department’s commitment to getting dangerous criminals and drugs off the streets,” Commissioner Edward F. Davis said at a press conference at police headquarters, where he was flanked by supervisors from the gang and drug units. “Today’s arrests will give residents back their neighborhoods.”

But four months later, it is unclear whether Operation H, named for the Humboldt Avenue section of Roxbury where the arrests were targeted, made the streets safer or even removed many criminals from the street, according to crime statistics and a review of the court records of those caught up in the sweep.

Forty of the 85 people targeted were quickly released on personal recognizance or given bail as low as $150, and those ordered held on higher sums were bailed out within weeks of their arrests.

Three of the targeted individuals were never even arrested; they received only citations for driving infractions, according to a Boston Globe review of court records.

One of them was Jeremy Harris, a 23-year-old Brockton man who was issued a citation for driving with a revoked driver’s license. On July 20, two months after Operation H was announced to the public, Harris allegedly fired eight shots into a crowd of people on Eustis Street in Roxbury. He was arrested by a Boston police gang unit detective who said he saw him flee the scene in a green Honda.

The shooting was part of a spike in summer violence that greatly affected Roxbury, the district targeted by the sweep. There were 35 shootings in the district during the months of June, July, and August, nearly twice as many as during the same period in 2012 and five more than in summer 2010, when the city saw an unusually big spike in homicides.

‘These raids, they are temporary fixes and publicity stunts.’

The homicide statistics for this year are murkier. There had been 15 homicides in the district through Aug. 26, seven more than last year in the same time period, with three occurring after Operation H, according to the most recent figures available from Boston police.

“These raids, they are temporary fixes and publicity stunts,” said the Rev. James Hills, a Jamaica Plain pastor and member of the Grove Hall Trust, which provides grant money to community groups in the Humboldt Avenue area of Roxbury. “From what I’m seeing, [Operation H] really didn’t have that much of an impact.”

Davis acknowledged a spike in violence at the beginning of the summer, but said he believed the operation had its intended effect.

Davis also said the number of shootings across the city slowed after the end of July.

“We’ve had a very good summer,” Davis said. “In spite of the fact that the numbers are up right now, I think that that trend has been coming down dramatically over the last couple of months.”

He justified the inclusion of people cited for minor infractions, like Harris’s driving citation, saying the goal of the operation was to warn criminals they were being watched.

“We’re not in this business to get long prison terms; we’re in it to change behavior,” he said. “If a motor vehicle ticket can let people know we’re out there, that can be very effective.”

Boston police have long embraced a philosophy that tries to change violent behavior in part through the threat of long prison sentences, most famously during the so-called “Boston Miracle” of the 1990s, when murder rates tumbled.

Jake Wark — spokesman for Suffolk District Attorney Daniel F. Conley, whose office prosecuted a large number of the suspects — said residents in the neighborhood had called police, demanding they intervene in what they saw as an open-air drug bazaar.

“It was tackled not only to improve the quality of life for the residents who made those phone calls, but also to disrupt a drug network that affects that neighborhood and sends drugs across the city,” Wark said.

He said prosecutors unsuccessfully asked for higher bails for the defendants who were arraigned in district courts. The majority of arrested during the sweep were arraigned in district court, though four faced charges in federal court and 14 were indicted in Suffolk Superior Court.

In the last year, the Legislature has passed laws amending mandatory drug sentences that reduced prison time for certain offenses.

“As a result, judges may be less inclined to impose high bail on drug cases, which translates to it being really harder than ever to obtain a lengthy prison sentence,” Wark said. But he said that focusing criminal investigations on drugs remains critical, noting that murders in the city are often drug-related.

Fifteen of the suspects remain incarcerated as they await trial, including four charged with gun offenses. One person was sentenced to 2½ years in county jail for charges including intimidation of a witness.

While the number of homicides in Roxbury were up through August, officials noted that generally homicides are down across the city. Through Sept. 9, there have been 35 homicides in the city, compared with 37 at the same time last year. The most recent killing was Saturday night on Blue Hill Avenue and Castlegate Road in Dorchester.

But the number of incidents in which a person was killed or struck by gunfire increased 13 percent through Aug. 26, the most recent numbers available in this category, from 164 to 185 shootings.

Operation H began as a small investigation last December, targeting drug dealers. But police decided to pour in more resources after the Jan. 11 shooting of Gabriel Clarke, a 13-year-old boy who was struck as he crossed Humboldt Avenue on his way to church choir practice. He survived, but the attack emboldened police, Davis has said.

For four months, police arrested dozens of men and women, picking many of them up on various drug charges. On May 21, they swept through several Boston neighborhoods in an early-morning raid that netted 33 people. An additional 52 people were charged during the investigation in the preceding months or had warrants issued for them. The majority of offenses were for drugs, ranging from cocaine possession to heroin distribution.

The goal of the raids was not only to put other criminals on notice that the same thing could happen to them, but also to pressure those arrested to provide information about Clarke’s shooting. The attack on Clarke, believed to be related to an ongoing gang feud in the Humboldt Avenue area, remains unsolved.

The Rev. Miniard Culpepper, pastor of Pleasant Hill Baptist Church on Humboldt Avenue, has worked for years with many of the teenagers and young men identified by police as gang members or drug dealers.

Some of those swept up said spending even a few nights in jail was sobering.

“I think for some of the kids, it definitely opened their eyes,” Culpepper said. “They don’t want to go back that way.”

But he said he expected police to follow up with other efforts, as they had in previous years, such as meeting with him and explaining their strategies to combat violence and introducing him to new detectives. That did not happen, with unfortunate consequences, said Culpepper.

He said that early in the summer, officers new to the district stopped by the park adjacent to his church, where Culpepper runs his summer peace program, and demanded to search the young men who had gathered there to pray and eat a warm dinner.

“We had no idea what was going on,” Culpepper said. “This was a very tough summer with the police. This was the first summer where they focused more on enforcement than on community policing.”

Davis said the officers acted appropriately in that instance because the area was a hotbed for shootings. He said that officers worked hard to collaborate with community leaders and ministers in the city’s more violent neighborhoods.

During the May press conference, officials said that young relatives of those arrested in the sweep would be referred to social service programs.

They ultimately referred to YouthConnect, an intervention program run by the Boys & Girls Club of Boston that connects young people with social workers, job training, and educational opportunities. Thirteen people went to the program for help.

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